Selective geometry for near-field three-dimensional localisation using one-pair sensor

Three-dimensional (3D) localisation of a single source in the near-field using one-pair sensor (a velocity-sensor triad and a pressure sensor) is considered. Recently, a new work has considered this problem and a method is developed with assumption that source target is closer to velocity-sensor triad than the pressure sensor. Since a prior knowledge of the target direction is not available in real situations, this algorithm cannot be applicable. In this study, a new geometry is proposed by adding another pressure sensor to the previous geometry to reduce its fundamental requirement of a known prior source direction. Then, a novel algorithm is proposed in which the velocity-sensor triad with only one of two pressure sensors is used for target localisation. By mathematical tractability of the proposed method, a selection rule for using suitable pair of sensor nodes is developed to hold the best estimation of the source location. It is shown that the proposed method not only has a solution in all target situations but also has better source estimation in comparison with the existing one. The simulation results on prototype data demonstrate the effectiveness of the proposed method in terms of existence and the accuracy of estimated target range.